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        <p>Library Version 11.2.5.3</p>
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            <h2 class="title" style="clear: both"><a id="stl_container_specific"></a>Dbstl container specific notes</h2>
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          <dt>
            <span class="sect2">
              <a href="stl_container_specific.html#idp51492808">db_vector specific notes</a>
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          <dt>
            <span class="sect2">
              <a href="stl_container_specific.html#idp51561456">Associative container specific notes</a>
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              <h3 class="title"><a id="idp51492808"></a>db_vector specific notes</h3>
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              <p>
                Set the <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> flag in the database handle if you want
                <code class="classname">db_vector&lt;&gt;</code> to work like
                <code class="classname">std::vector</code> or <code class="classname">std::deque</code>.  Do not set
                <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> if you want <code class="classname">db_vector&lt;&gt;</code> to work like
                <code class="classname">std::list</code>. Note that without <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set,
                <code class="classname">db_vector&lt;&gt;</code> can work faster.
            </p>
              <p>
                For example, to construct a fast std::queue/std::stack object, you only need a
                <code class="classname">db_vector&lt;&gt;</code> object whose database handle does not have
                <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set.  Of course, if the database handle has <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set, it
                still works for this kind of scenario, just not as fast.
            </p>
              <p>
                <code class="classname">db_vector</code> does not check whether <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> is set.  If
                you do not set it, <code class="classname">db_vector&lt;&gt;</code> will not work like
                std::vector&lt;&gt;/std::deque&lt;&gt; with regard to operator[], because the
                indices are not maintained in that case.
            </p>
              <p>
                You can find example code showing how to use this feature in the
                <code class="methodname">StlAdvancedFeaturesExample::queue_stack()</code> method.
            </p>
            </li>
            <li>
              <p>
                Just as is the case with <code class="classname">std::vector</code>, inserting/deleting in
                the middle of a <code class="classname">db_vector</code> is slower than doing the same
                action at the end of the sequence. This is because the underlying DB_RECNO DB (with
                the <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> flag set) is relatively slow when inserting/deleting in the middle
                or the head — it has to update the index numbers of all the records following
                the one that was inserted/deleted. If you do not need to keep the index ordered on
                insert/delete, you can use <code class="classname">db_map</code> instead.
            </p>
              <p>
                <code class="classname">db_vector</code> also contains methods inherited from
                <code class="classname">std::list</code> and <code class="classname">std::deque</code>,
                including <code class="classname">std::list&lt;&gt;'s</code> unique methods
                <code class="methodname">remove()</code>, <code class="methodname">remove_if()</code>,
                <code class="methodname">unique()</code>, <code class="methodname">merge()</code>,
                <code class="methodname">sort()</code>, <code class="methodname">reverse()</code>, and
                <code class="methodname">splice()</code>. These use the identical semantics/behaviors
                of the <code class="classname">std::list&lt;&gt;</code> methods, although
                pushing/deleting at the head is slower than the
                <code class="methodname">std::deque</code> and <code class="methodname">std::list</code> 
                equivalent when there are quite a lot of elements in the database.
            </p>
            </li>
            <li>
              <p>
                You can use <code class="classname">std::queue</code>,
                <code class="classname">std::priority_queue</code> and <code class="classname">std::stack</code>
                container adapters with <code class="classname">db_vector</code>; they work with db_vector
                even without <a href="../api_reference/C/dbset_flags.html#dbset_flags_DB_RENUMBER" class="olink">DB_RENUMBER</a> set.
            </p>
            </li>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
          <div>
            <div>
              <h3 class="title"><a id="idp51561456"></a>Associative container specific notes</h3>
            </div>
          </div>
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        <p>
        <code class="classname">db_map</code> contains the union of method set from
        <code class="classname">std::map</code> and <code class="classname">hash_map</code>, but there are some
        methods that can only be called on containers backed by <code class="literal">DB_BTREE</code> or
        <code class="literal">DB_HASH</code> databases.  You can call
        <code class="function">db_map&lt;&gt;::is_hash()</code> to figure out the type of the backing
        database. If you call unsupported methods then an InvalidFunctionCall exception is thrown. 
	</p>
        <p>
        These are the <code class="literal">DB_BTREE</code> specific methods: <code class="methodname">upper_bound()</code>,
        <code class="methodname">lower_bound()</code>, <code class="methodname">key_comp()</code>,
        and <code class="methodname">value_comp()</code>. The <code class="literal">DB_HASH</code> specific methods are
        <code class="methodname">key_eq()</code>, <code class="methodname">hash_funct()</code>.
	</p>
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